Merge branch 'master' into 'master'

Update mail_room gem

## What does this MR do?

Upgrades the mail_room gem from 0.8.0 to 0.8.1.

## Why was this MR needed?

mail_room throws an exception if the watching script joins a undefined thread. Release 0.8.1 adds a check to ensure that the thread exists before calling join.

Fixes gitlab-org/omnibus-gitlab#1619.

See merge request !6714

CHANGELOG

@@ -93,6 +93,7 @@ v 8.13.0 (unreleased)
   - API: all unknown routing will be handled with 404 Not Found
 
 v 8.12.5 (unreleased)
+  - Update the mail_room gem to 0.8.1 to fix a race condition with the mailbox watching thread
 
 v 8.12.4
   - Fix "Copy to clipboard" tooltip to say "Copied!" when clipboard button is clicked. !6294 (lukehowell)

Gemfile

@@ -324,7 +324,7 @@ gem 'newrelic_rpm', '~> 3.16'
 
 gem 'octokit', '~> 4.3.0'
 
-gem 'mail_room', '~> 0.8'
+gem 'mail_room', '~> 0.8.1'
 
 gem 'email_reply_parser', '~> 0.5.8'
 

Gemfile.lock

@@ -889,7 +889,7 @@ DEPENDENCIES
   license_finder (~> 2.1.0)
   licensee (~> 8.0.0)
   loofah (~> 2.0.3)
-  mail_room (~> 0.8)
+  mail_room (~> 0.8.1)
   method_source (~> 0.8)
   minitest (~> 5.7.0)
   mousetrap-rails (~> 1.4.6)